• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 추계학술발표대회
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• pp.7.2-7.2
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• 2009

Nanoporous bioactive glass(NBG) ceramic with well interconnected pore structures were fabricated bytriblock copolymer templating and sol-gel techniques. Hierarchically porous BGbeads were also successfully synthesized by controlling the condition of solvent.The beads have hierarchically nano- and macro-pore structure with a sizesbetween several tens nanometers and several hundred micrometers. Both NBG andBG beads show superior bone-forming bioactivity and good in vitrobiodegradability. Biocompatibility both in vitro and in vivo were examed andwas revealed that it largely relies on the pore morphology as well ascomposition. Our synthetic process can be adapted for the purpose of preparingvarious bioceramics, which have excellent potential applications in the fieldof biomaterials such as tissue engineering and drug storage.

• 한국세라믹학회지
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• 제30권6호
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• pp.433-440
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• 1993

The bioactivity of glasses in the CaO-SiO2 system and CaO-P2O5-SiO2 system with less than 10mol% of P2O5 was investigated by in vitro test in simulated body flood(SBF). The formation of Ca.P film and hydroxyapatite on the surface of glasses after in vitro test was analysed by X-ray photoelectron spectoscopy (XPS), fourier transform infrared reflection spectroscopy (FT-IRRS), energy dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM) observation. In the early stage of Ca.P film formation after in vitro test for CaO-SiO2 and CaO-P2O5-SiO2 glasses, the rate of Ca.P film formation on the surface of the glasses was dependent of structural parameter (Y) evaluated from the glass composition. First, in the case of the glasses having Y value below 2, Ca.P film and SiO2-rich layer were formed simultaneously, and there were no differences of the rate of Ca.P film formation in terms of the Y values. Second, in the case of the glasses having Y value above 2, the SiO2-rich layer was formed, and then Ca.P.Si mixed layer was formed in the silica gel structure of the SiO2-rich layer, and finally the Ca.P film on the surface of SiO2-rich layer. The rate of Ca.P film formation delayed as the Y values increased. The rate of hydroxyapatite formation of glasses (the rate of transformation from Ca.P film to hydroxyapatite) seems to be propotional to the rate of Ca.P film formation and Y value. The rate of hydroxyapatite formation of glasses belonging to the second group was delayed as structural parameter increased, and the hydroxyapatite crystal showed spherical growth in the early reaction stage, and then showed silkworm-like linear growth as the reaction time increased.

• 한국결정성장학회지
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• 제22권2호
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• pp.99-104
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• 2012

BCP(biphasic calcium phosphate) 분말을 제조하기 위하여 $Ca(NO_3)_2{\cdot}4H_2O$, $(NH_4)_2HPO_4$를 출발 물질로 공침법(co-precipitation process)을 이용하여 합성하였다. 합성된 분말의 열처리 전 후의 HAp(Hydroxyapatite)/${\beta}$-TCP(${\beta}$-Tricalcium phosphate) 결정상 비율 및 분광학적 특성을 XRD 및 FT-IR를 이용하여 분석하였다. BCP 분말의 생체활성 거동을 평가하기 위하여 Hanks' Balanced Salt Solution(HBSS)에 침적시켜 시간에 따라 형상, 이온농도의 변화 및 결정상을 분석한 결과 낮은 결정화도의 HAp가 생성됨을 확인하였다. BCP분말의 세포독성 평가에서도 대조군에 비하여 세포성장률이 우수함을 관찰하였다.

• 한국결정성장학회지
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• 제20권5호
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• pp.243-248
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• 2010

Si-BCP(si-substituted biphasic calcium phosphate)를 제조하기 위하여 $Ca(NO_3)_2{\cdot}4H_2O$, $(NH_4)_2HPO_4$, $Si(OC_2H_5)_4$을 출발 물질로 공침법(co-precipitation process)을 이용하여 합성하였다. 합성된 분말의 HAp/${\beta}$-TCP 결정상 비율 및 Si-P 치환 거동은 X-선 회절 상 분석을 이용하여 측정하였고, silicon ion 첨가 시 나타나는 BCP의 화학적 결합거동을 측정하기 위하여 FT-IR를 사용하여 분석하였다. 또한 Si-BCP 분말의 in-vitro 생분해거동 및 생체활성도를 측정하기 위하여 제조된 분말을 SBF(simulated body fluid) solution에 침적시킨 뒤 분말의 형상과 구성 성분은 SEM과 EDS를 통하여 확인하였다.

• 한국표면공학회지
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• 제56권4호
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• pp.273-282
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• 2023

In this study, the surface of Polyetheretherketone (PEEK) disks was modified to have a hydrophilic surface by applying a coating of Polyethylene glycol (PEG), Hyaluronic acid(HA), and Poly-Dopamine(PDA). The investigation aimed to examine whether the coated surfaces showed enhanced bioactivity for orthopedic applications compared to the pure PEEK. The microstructure, surface characteristics, and wettability of PEEK coated with PEG, HA, and PDA were analyzed using scanning electron microscopy(SEM), FT-IR spectrophotometer, Roughness Measurement System, Micro-Vickers, and Contact angle measurement. The mechanical properties were analyzed using a tensile testing machine, while the MTT assay for cell activity was analyzed using a microplate reader to measure optical density. According to the SEM and FT-IR results, the composition and crystal structure of PEG, HA and PDA coated surface were verified. Also, roughness, hardness, and contact angle were all improved in the coating group compared to the pure PEEK. We checked the HepG2 cell proliferation by using MTT assay on 7th days. In MTT assay results, HepG2 cell proliferation was increased with time, at 7 days, cell viability on discs coated with PDA was significantly higher than pure PEEK, PEG, HA coated group. PDA coated PEEK exhibited the highest surface roughness, hardness, contact angle, and cell activity. The mechanical properties were not affected by the presence of the coating.

• Natural Product Sciences
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• 제13권3호
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• pp.247-250
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• 2007

A new sphingosine (1) was isolated from the MeOH extract of a marine sponge Haliclona (Reniera) sp. by bioactivity-guided fractionation. The 1D and 2D NMR, and MS spectroscopic analyses were used to establish the planar structure of 1. The stereochemistry of the compound was defined on the basis of modified Mosher's method, comparison of optical rotation and NMR data with those of the reported. Compound 1 was mildly cytotoxic to a panel of five human solid tumor cell lines.

• 통합자연과학논문집
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• 제7권3호
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• pp.159-165
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• 2014

Pyrazole, hydroxyimino, aldehyde and isoxazole derivatives exhibit a broad spectrum of biological activities such as antimicrobial, anti-inflammatory and antitumor activities. With growing application on their synthesis and bioactivity, chemists and biologists in recent years have considerable attention on the research of these derivatives. In the view of potential importance of these derivatives, we have crystallized few of the derivatives and its report has been published. The present study focuses on docking studies of these derivatives against Phospholipases $A_2$ enzyme. This enzymes has implicated as potential targets for anti-inflammatory drug design. co-crystal structure (PDB ID: 1POE) of $PLA_2$ deposited in Protein Data Bank has been retrieved for docking analysis. Docking studies using Schrodinger's GLIDE reveals that these derivatives shows better binding energy and score in the defined active site. These results may provide a guiding role to design a lead molecule which may reduce inflamation.

• 대한치과의사협회지
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• 제56권3호
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• pp.152-158
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• 2018

Polyaryletherketone (PAEK) is recently introduced in dentistry. The polymer has superior mechanical and chemical properties compared to previous dental materials. PAEK has been explored for lots of applications for clinical dentistry. The prostheses can be made by the injection molding or milling techniques. Recent studies focus on improving the bioactivity of PAEK and expanding the application. The purpose of this article is to introduce the basic features, chemical structure and various clinical applications in fixed dental prostheses. Further research and clinical trials will be needed to confirm the usability of PAEK in the routine practice.

• Natural Product Sciences
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• 제9권4호
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• pp.232-234
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• 2003

A new glycerol ether has been isolated from a marine sponge Stelletta sp. By bioactivity-guided fractionation. The structure was established on the basis of NMR and MS analyses. The compound was evaluated for cytotoxicity against a small panel of five human tumor cell lines and exhibited significant cytotoxicity.

• Bulletin of the Korean Chemical Society
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• 제26권3호
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• pp.447-450
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• 2005

The crude methanol extract of the fruits of Amomum tsao-ko (Zingiberaceae) showed cytotoxic activity. Bioactivity-guided separation led to the isolation of a diarylheptanoid, tsaokoarylone [7-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)-hepta-4E,6E-dien-3-one] (2). 2 showed cytotoxicity at 4.9 and 11.4 $\mu$g/mL ($IC_{50}$) against human nonsmall cell lung cancer A549 and human melanoma SK-Mel-2, respectively, determined by SRB colorimetric method. During purification-(4-hydroxyphenyl)-4-hydroxyhexan-2-one (4) together with three known diarylheptanoids was also isolated. Their structures were determined from interpretation of spectroscopic data (IR, UV, MS, and NMR) and synthesis confirmed the structure of 2.